检索结果-南通市图书馆

Journal of Innovative Optical Health Sciences 2013年第4期6卷 84-90页

作者： JIANHUA YIN YANG xia ZHIYAN xiao Department of Biomedical Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 P.R.China Department of Physics and Center for Biomedical Research Oakland University RochesterMI 48309USA Department of Radiation Oncology Washington University School of Medicine St.Louis MO 63110USA

Fourier transform infrared imaging(FTIRI)was used to examine the depth-dependent content variations of macromolcular components,ollagen and protooglycan(PG),in osteoarthritic and healthy *** 6 pmm thick sections of canine knee cartilages were imaged at 6.25 pμrm pixel-size in *** analyzing the infrared(IR)images and spectra,the depth dependence of characteristic band(sugar)intensity of PG show obvious difference bet ween the cartilage sections of(OA)and *** result confimns that PG content decreases in the ostcoarthritic ***,no clear change occurs to collagen,suggesting that the OA influences little on the collagen content at early stage of *** observation will be helpful to further understand PG loss associated with pathological conditions in OA,and demonstrates that FIIRI has the po-tential to become an important analytical tool to identify early clinical signs of tissue degna-dation,such as PG loss even collagen disruption.

关键词： Macromolecular component osteoarthritis articular cartilage Fourier transform infrared imaging(FTIRI)

Unusual photocarrier and coherent phonon dynamics behaviors of layered PdSe_(2)unveiled by ultrafast spectroscopy of the edge surface

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 143-152页

作者： Tiantian Yun Changfu huo Jinluo Cheng Zhi-Bo Liu xiao-Qing Yan Key Laboratory of Weak-Light Nonlinear Photonics Ministry of EducationSchool of PhysicsNankai UniversityTianjin 300071China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China GPL Photonics Laboratory Key Laboratory of Luminescence Science and TechnologyChinese Academy of Sciences&State Key Laboratory of Luminescence Science and ApplicationsChangchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

Layered materials exhibit different electronic and phonon properties along in-plane and out-of-plane directions;existing studies focus on their in-plane behaviors,and the influence of such anisotropies on the dynamics of photocarriers and phonons is ***,we fabricate layered PdSe_(2)crystals with flat edge surfaces and compare the time-resolved ultrafast spectroscopies on their basal and edge *** differences in the transient reflection spectroscopies reveal the inconsistent photocarrier and phonon dynamics behaviors on the two surfaces:the slow hot carrier relaxation process is accelerated and the thermoelasticity-induced longitudinal coherent acoustic phonon oscillation completely vanishes on the edge surface,as compared with the basal *** analysis reveals that the inconsistent hot carrier dynamics originate from the anisotropic properties of low-energy phonons in PdSe_(2),and the absence of phonon oscillation on the edge surface results from the wavevector-limited sensitivity of acoustic B_(1u)***,polarization-dependent spectroscopies indicate the diverse optical anisotropies beyond the in-plane of PdSe_(2).This work provides a new method to explore unique physical properties and modulate the optical anisotropy of layered materials.

关键词： PdSe_(2) ultrafast spectroscopy edge surface carrier dynamics coherent phonon oscillation anisotropy

Empirical Likelihood for Partially Linear Errors-in-variables Models with Longitudinal Data

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2022年第3期38卷 664-683页

作者： Li YAN xiao-yan TAN xia CHEN School of Mathematics and Statistics Shaanxi Normal UniversityXi’an 710119China

Empirical likelihood inference for partially linear errors-in-variables models with longitudinal data is *** regularity conditions,it is shown that the empirical log-likelihood ratio at the true parameters converges to the standard Chi-squared ***,we consider some estimates of the unknown parameter and the resulting estimators are shown to be asymptotically *** simulations and a real data analysis are given to illustrate the performance of the proposed method.

关键词： empirical likelihood measurement error confidence regions coverage probability longitudinal data

Dynamic simulation and optimal control strategy for a parallel hybrid hydraulic excavator

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第5期9卷 624-632页

作者： xiao LIN Shuang-xia PAN Dong-yun WAN State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

The primary focus of this study is to investigate the control strategies of a hybrid system used in hydraulic excavators. First, the structure and evaluation target of hybrid hydraulic excavators are analyzed. Then the dynamic system model including batteries, motor and engine is built as the simulation environment to obtain control results. A so-called multi-work-point dynamic control strategy, which has both closed-loop speed PI (proportion integral) control and direct torque control, is proposed and studied in the simulation model. Simulation results indicate that the hybrid system with this strategy can meet the power demand and achieve better system stability and higher fuel efficiency.

关键词： Hybrid system Hydraulic excavator Multi-work-point dynamic control Direct torque control

UAV Communications with Millimeter-Wave Beamforming:Potentials,Scenarios,and Challenges

在线全文

学校读者我要写书评

暂无评论

China Communications 2020年第9期17卷 147-166页

作者： Zhenyu xiao Lipeng Zhu xiang-Gen xia School of Electronic and Information Engineering Beihang UniversityBeijing 100191China Department of Electrical and Computer Engineering University of DelawareNewarkDE 19716USA

Unmanned aerial vehicle(UAV)has been widely used in many fields and is arousing global *** the resolution of the equipped sensors in the UAV becomes higher and the tasks become more complicated,much higher data rate and longer communication range are required in the foreseeable *** the millimeter-wave(mm Wave)band can provide more abundant frequency resources than the microwave band,much higher achievable rate can be guaranteed to support UAV services such as video surveillance,hotspot coverage,and emergency communications,*** flexible mm Wave beamforming can be used to overcome the high path loss caused by the long propagation *** this paper,we study three typical application scenarios for mm Wave-UAV communications,namely communication terminal,access point,and backbone *** present several key enabling techniques for UAV communications,including beam tracking,multi-beam forming,joint Tx/Rx beam alignment,and full-duplex relay *** show the coupling relation between mm Wave beamforming and UAV positioning for mm Wave-UAV ***,we summarize the challenges and research directions of mm Wave-UAV communications in detail.

关键词： unmanned aerial vehicle(UAV) millimeter-wave(mmWave)communications beamforming beam tracking deployment

Paleoceanographic records and sea ice extension history on the slope of the northern Bering Sea over the last 100 ka B.P.

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2005年第6期24卷 117-126页

作者： WANG Rujian LI xia xiao Wenshen xia Peifen CHEN Ronghua State Key Laboratory of Marine Geology Tongji University Shanghai 200092China State Key Laboratory of Marine Geology Tongji University Shanghai 200092China State Key Laboratory of Marine Geology Tongji University Shanghai 200092China State Key Laboratory of Marine Geology Tongji University Shanghai 200092China Key Laboratory of Submarine Geoscience State Oceanic Administration Hangzhou 310012China

Quantitative analytic results of the biogenic components in Core B2-9 fromthe northern Bering Sea slope indicate that the coarse fraction and opal content, serving as proxiesof surface productivity, have increased stepwise since the marine isotope stageCMISJS.S, reflectingperiodic enhancement in surface *** surface productivity attained its highest levelduring the Holocene, followed by MIS 3.2 to 2 and then MIS 5.3 to 3.3 with a lowest level. Hightotal organic carbon(TOC) contents, together with high C/N ratios, which stand mostly between 7 and20, show that the TOC was deposited from mixing sources. Therefore,one has to be cautious to use TOCas a proxy of surface *** high TOC and C/N ratio during MIS 5.1, 3.3 to 3.2 and theHolocene reflect that the terrigenous organic matter input increased during *** in the fine- and silt-grained terrigenous components from MIS 5.3 to the middleHolocene imply that with the cooling climate, sea ice on the Bering Sea slope extended ***-rafted and charcoal detritus increased during glacial, interstadial and the last deglaciationperiods and decreased during interglacial periods, suggesting that sea ice on the slope increasedand melted, respectively, during glacial and interglacial periods. The extension of sea ice duringglacial *** was linked with the climate over the North American Continent, responded toglobal climate change during late Quaternary glacial and interglacial cycles.

关键词： surface productivity ice-rafted detritus sea ice extension history latequaternary bering sea

New forming method of manufacturing cylindrical parts with nano/ultrafine grained structures by power spinning based on small plastic strains

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2016年第11期59卷 1656-1665页

作者： xiao GangFeng xia Qinxiang CHENG XiuQua LONG Hu School of Mechanical and Automotive Engineering South China University of Technology Department of Aircraft Maintenance Engineering Guangzhou Civil Aviation College Department of Mechanical Engineering The University of Sheffield

A new spinning method to manufacture the cylindrical parts with nano/ultrafine grained structures is proposed, which consists of quenching, power spinning and recrystallization annealing. The microstructural evolution during the different process stages and macroforming quality of the spun parts made of ASTM 1020 steel are investigated. The results show that the microstructures of the ferrites and pearlites in the ASTM 1020 steel are transformed to the lath martensites after quenching. The martensite laths obtained by quenching are refined to 87 nm and a small amount of nanoscale deformation twins with an average thickness of 20 nm is generated after performing a 3-pass stagger spinning with 55% thinning ratio of wall thickness, where the equivalent strain required is only 0.92. The equiaxial ferritic grains with an average size of 160 nm and nano-carbides are generated by subsequent recrystallization annealing at 480°C for 30 min. The spun parts with high dimensional precision and low surface roughness are obtained by the forming method developed in this work, combining quenching with 3-pass stagger spinning and recrystallization annealing.

关键词： nano/ultrafine grained structure cylindrical parts quenching power spinning recrystallization annealing small plastic strain

Autophagy in plants: Physiological roles and post-translational regulation

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Plant Biology 2021年第1期63卷 161-179页

作者： Hua Qi Fan-Nv xia Shi xiao State Key Laboratory of Biocontrol Guangdong Provincial Key Laboratory of Plant ResourcesSchool of Life SciencesSun Yat-sen UniversityGuangzhou 510275China

In eukaryotes, autophagy helps maintain cellular homeostasis by degrading and recycling cytoplasmic materials via a tightly regulated *** the past few decades, significant progress has been made towards understanding the physiological functions and molecular regulation of autophagy in plant cells. Increasing evidence indicates that autophagy is essential for plant responses to several developmental and environmental cues, functioning in diverse processes such as senescence, male fertility, root meristem maintenance, responses to nutrient starvation,and biotic and abiotic stress. Recent studies have demonstrated that, similar to nonplant systems,the modulation of core proteins in the plant autophagy machinery by posttranslational modifications such as phosphorylation, ubiquitination,lipidation, S-sulfhydration, S-nitrosylation, and acetylation is widely involved in the initiation and progression of autophagy. Here, we provide an overview of the physiological roles and posttranslational regulation of autophagy in plants.

关键词： autophagy physiological roles post-translational regulation

Coordinated Planning for Fast Charging Stations and Distribution Networks Based on an Improved Flow Capture Location Model

在线全文

学校读者我要写书评

暂无评论

CSEE Journal of Power and Energy Systems 2023年第4期9卷 1505-1516页

作者： Shiqu xiao xia Lei Tao Huang xiang Wang School of Electrical Engineering and Electronic Information Xihua UniversityChengdu 610039China. Department Ingegneria Elettrica Politecnico Di TorinoTorino 10129Italy

The increasing penetration of plug-in electric vehi-cles(PEVs)should lead to a significant reduction in greenhouse gas ***,the development of PEVs is limited by the lack of charging facilities,which is constrained by the coupled transportation-distribution *** paper presents a stochastic bi-level model for the optimal allocation of fast charging stations(FCSs)and distribution network expansion planning(DNEP).First,a sequential capacitated flow-capturing location-allocation model(SCFCLM)is proposed at the lower level to optimize the allocation of FCSs on the transportation ***-Carlo simulation(MCS)is utilized to estimate daily charging load ***,we propose an economic model for DNEP at the upper level,and the chance constrained method is employed to relax power flow constraints to address the uncertainties of *** experiments are conducted to illustrate the proposed planning *** influences of the flow capturing sequence and relaxed confidence level on the PEV charging load,FCS planning strategies and DNEP schemes are *** Terms-Coordinated planning,fast charging station,flow-capturing model,plug-in electric vehicle,stochastic bi-level model.

关键词： Coordinated planning fast charging station flow-capturing model plug-in electric vehicle stochastic bi-level model.

Harmonic Transfer Function Based Single-input Single-output Impedance Modeling of LCC-HVDC Systems

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1327-1332页

作者： Yang Wang Fei xia Ying Wang xianyong xiao College of Electrical Engineering Sichuan UniversityChengdu 610065China

This study presents a harmonic transfer function(HTF)based single-input single-output(SISO)impedance modeling *** method converts an HTF from phase domain to sequence domain and then transforms it into an SISO impedance while preserving the frequency coupling information of different sequences and different *** of this method to a line-commutated converter based high-voltage direct current(LCC-HVDC)system are *** results demonstrate the accuracy of the derived SISO impedance,and a truncation-order selection is *** case study shows that the proposed method facilitates simpler impedance measurements and associated stability analysis.

关键词： Line-commutated converter based high-voltage direct current(LCC-HVDC) harmonic transfer function(HTF) single-input single-output(SISO)impedance frequency coupling